It is common to harvest and then ship bananas while the peels are green. It is also common, once the bananas have reached a location near where they will be sold, to place them in an enclosed volume and expose them to ethylene gas. After the exposure to ethylene, the normally ripen more quickly. As the bananas ripen, the peels gradually turn yellow; the peels remain yellow for some time; then the peels develop black spots; and eventually the bananas become undesirably over-ripe.
Bananas are prone to various problems. One such problem is premature ripening, which sometimes occurs during shipment. It is desired that the bananas have a green life (i.e., the time during which they remain green) that is longer than the shipping time. Sometimes, events can shorten the green life of bananas. For example, if, during shipment, the interior of a container of bananas is exposed to ethylene gas, many of the bananas will ripen prior to arrival at their destination, and many of those bananas will need to be discarded. This premature ripening causes significant losses to the banana industry.
The problem of premature ripening is exacerbated if the bananas were stressed prior to harvest. Stress can arise from a variety of causes, including, for example, flooding or disease (such as, for example, black Sigatoka) or other stress factors or combinations thereof. It is considered that stressed bananas will normally have a shortened green life. Commonly, when stress is observed, the bananas are harvested early, which helps to extend the green life, but the early harvesting causes a reduction in size of the bananas and in crop yield.
Another common problem is that bananas have a relatively short yellow life. That is, while bananas are on display in a retail setting, they are desirable to consumers during their “yellow life” (i.e., from the time the peels start to turn yellow until the bananas become over-ripe). Because the yellow life is often very short, many bananas reach the end of their yellow life before they are sold and have to be discarded, which also causes losses to the banana industry.
US 2005/0261132 discloses treating plants or plant parts with liquid composition containing metal-complexing agent. It is desired to provide a method of treating bananas in particular that will improve the green life or the yellow life or both. It is also desired to provide a method that can be used to treat bananas that were stressed during harvest and can thereby overcome the necessity of harvesting such bananas early.